1. Field of the Invention
The present invention relates to a fluorine-containing elastomer composition, and more particularly to a cross-linkable composition of fluorine-containing elastomer having cyano groups as cross-linkable groups.
2. Related Prior Art
JP-A-59-109546 discloses a fluorine-containing elastomer composition comprising a terpolymer of tetrafluoroethylene, perfluoro(methyl vinyl ether) and cyano group-containing (perfluorovinylether) represented by the following general formula: EQU CF.sub.2 .dbd.CF[OCF.sub.2 CF(CF.sub.3)]nO(CF.sub.2)mCN
wherein n is an integer of 1 to 2 and m is an integer of 1 to 4, and a bis(aminophenyl) compound represented by the following general formula as a cross-linking agent: ##STR1## wherein A is an alkylidene group having 1 to 6 carbon atoms, a perfluoroalkylidene group having 1 to 10 carbon atoms, SO.sub.2 group, O group, CO group or a carbon-carbon bond capable of directly bonding two benzene rings, and X and Y each are hydroxyl group or amino group. However, the bis(diamino-phenyl) compound or bis(aminophenol) compound is expensive for the industrial scale application.
JP-A-55-98212 discloses use for tetraphenyl tin as a curing agent for such a fluorine-containing elastomer having cyano groups, but the tetraphenyl tin is toxic and its use is not preferable.